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反应堆压力容器属于一级安全设备,在各种运行工况和试验条件下均要保持结构的完整性,不会发生放射性物质的泄漏[1,2]。压力容器承受包括压力、热膨胀等复杂载荷,它的密封性是保证核电站安全运行的关键因素之一[3,4]。因此对其密封性进行系统深入地研究具有重要的工程意义。
文献[5]使用有限元法对反应堆压力容器国产化O形密封环进行了大变形弹塑性接触分析。自编程序或借助于ANSYS,采用弹塑性小变形问题的非线性求解方法、接触问题的混合求解算法等方法完成三维瞬态密封分析[6]。
为保证压力容器的密封性能,需要对螺栓预紧过程进行数值模拟。文献[3]分析了CPR 1000反应堆压力容器主螺栓预紧的过程,高温气冷堆压力容器承压螺栓预紧过程得到有限元模拟,同时压水堆反应堆压力容器密封主螺栓预紧过程也得到模拟。但如何才能找出最合理的预紧方案,保证最终螺栓预紧力分布的均匀性,还需要进一步探索。
由于反应堆压力容器存在超大的模型规模、壳体之间存在多个法兰对接触、大量螺栓预紧力模拟等特征,常规有限元分析软件在现有硬件条件下进行反应堆压力容器密封分析时对反应堆压力容器进行假设和简化。我们开发自主有限元软件,尽可能对反应堆压力容器进行整体建模,在进行不同工况下压力容器的应力和变形分析时考虑接触和螺栓预紧等关键问题。
本文中我们利用自主开发的结构有限元软件ATLAS[7,8]建立压力容器模型,对压力容器密封法兰的接触过程进行了数值模拟,得到了其受力特性和应力分布规律。同时,我们尝试使用ATLAS完成压力容器螺栓预紧的力学计算。我们首先对压力容器螺栓建立模型,然后对压力容器进行快速的有限元剖分,接着利用有限元求解器对该模型进行计算。最后我们对计算结果进行验证并讨论。
我们自主开发的结构有限元软件ATLAS根据结构有限元分析的应用特点,在创新的预排序文件缓存技术和三维渲染技术等方面做了大量的优化工作,能让CAE工程师在高度交互及可视化的环境下进行仿真分析工作。
Sealing Analysis of Reactor Pressure Vessel Based on ATLAS
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摘要:
[目的] 反应堆压力容器的密封性是保证核电站安全运行的关键因素之一,因此对其密封进行系统深入地研究具有重要的工程意义。自主开发的结构有限元软件ATLAS根据结构有限元分析的应用特点,在创新的预排序文件缓存技术和三维渲染技术等方面做了大量的优化工作,能让CAE工程师在高度交互及可视化的环境下进行仿真分析工作。 [方法] 利用ATLAS软件建立压力容器模型,对压力容器螺栓预紧力、密封法兰的接触过程进行了数值模拟,得到了其受力特性和应力分布规律。 [结果] 研究表明:ATLAS可以准确的导入模型,划分网格,施加各种工况,快速完成求解计算,很好的完成密封问题的有限元分析。计算结果的准确性能够得到保证,可以使用该方法进行压力容器的密封分析和应力校核。 [结论] ATLAS是一个适用于核电工程的大规模结构快速有限元分析系统,可以用来进行压力容器的接触分析和结构强度的校核,具有较好的应用前景。 Abstract:[Introduction] Sealing of reactor pressure vessel is one of the key factors in the safe operation of nuclear power plants, and therefore it has significant importance in engineering to conduct the in-depth study of its contacting systems. Based on the application characteristics of finite element analysis, we have developed independently a software ATLAS, where a lot of innovation optimizations have been done in terms of pre-sorted file caching and 3D rendering technologies that allows CAE engineers working in highly interactive and visual environments. [Method] In this paper we used ATLAS to create a pressure vessel model, and then simulated numerically the contacting and the sealing of pressure vessel, and finally obtained the mechanical characteristics and stress distribution, and evaluated the strength and fatigue analysis of its critical section. [Results] The results show that ATLAS can accurately import and mesh models, apply a variety of conditions, quickly complete finite element analy ele sis of contact problems. The accuracy of the results can be guaranteed, according to the methods, the designed flange meets the requirements of structural strength and durability. [Conclusion] As a rapid finite element analysis system for large-scale structures, ATLAS provides tools for structural sealing analysis and strength checking for reactor pressure vessel and it has good application prospects. -
Key words:
- reactor pressure vessel /
- structural finitement analysis /
- stress analysis /
- sealing
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[1] MOHAN K M, CHAKRABARTI S K, BASU P C, et al. Study of the linear behavior of a PSC containment dome with large openings [J]. Nuclear Engineering & Design, 2000, 196(2): 123-137. [2] NASSAR S A,ALKELANI A A. Clamp load loss due to elastic interaction and gasket creep relaxation in studed joints [J]. ASME J. Pressure Vessel Technol,2006,128(3):394-401. [3] 熊光明,邓小云,段远刚,等. CPR1000反应堆压力容器密封性能模拟技术研究 [J]. 核技术,2013,36(4):32-36. XIONG G M,DENG X Y,DUAN Y G,et al. Sealing behavior simulation technology research for CPR1000 reactor pressure vessel [J]. Nuclear Techniques,2013,36(4):32-36. [4] JIA X,CHEN H,LI X,et al. A study on the sealing performance of metallic C-rings in reactor pressure vessel [J]. Nuclear Engineering Design,2014,278(10):64-70. [5] 薛国宏,曹明,沈睿,等. 反应堆压力容器国产O形环密封性能分析 [J]. 压力容器,2016,33(3):16-20. XUE G H,CAO M,SHEN R,et al. Sealing behavior research on metal O-ring of reactor pressure vessel [J]. Pressure Vessel Technology,2016,33(3):16-20. [6] 邵雪娇,郑连纲,苏东川,等. 反应堆压力容器密封环有限元模拟技术研究 [J]. 核动力工程,2015,36(增刊2):142-145. SHAO X J,ZHENG L G,SU D C,et al. Study on finite simulation technology for seal ring of reactor pressure vessel [J]. Nuclear Power Engineering,2015,36(Supp.2):142-145. [7] WANG H, LÜ P. Performance improvement of seismic analysis in a large scale interactive visualization[C]//IEEE. 2015 IEEE 17th International Conference on High Performance Computing and Communications (HPCC), New York, U.S.A., Aug. 24-26, 2015. U.S.A.: IEEE, 2015:908-913. [8] WANG H, LÜ P. Evaluation of memory optimization in a large-scale structural finite element pre-processor [C]//IEEE. 2014 IEEE 8th International Symposium on Embedded Multicore/Manycore SoCs (MCSoC), Aizu-Wakamatsu, Japan, Sep. 23-25, 2014. U.S.A.: IEEE, 2014: 31-38.